<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>边框内圆角</title>
  <style>
    .test {
      background: tan;
      border-radius: .8em;
      padding: 1em;
      box-shadow: 0 0 0 .34em #655;
      outline: .6em solid #655;
    }
  </style>
</head>
<body>
  <div class="test">AAAAA</div>
</body>
</html>
